Apparatus for and method of controlling distortion



July 16,1940. w D v 2,208,121

APPARATUS FOR AND METHOD OF CONTROLLING DISTORTION Filed April 24, 1937 INVENTOR ARTHUR w DAVIS BY ATTORNEY u the invention; and

Patented July V16, 1940 UNITED STATE APPABATUS Fon AND METHOD OF CONTROLLING DISTOBTION Arthur w. Davis. Lakewood, Ohio, assignor'to The Linde Air Products Company, a corpora-' tion of Ohio Application April 24, 1937, Serial No. name This invention relates to apparatus ior and a method of controlling distortion of a metal part while it is being flame cut. The invention is vparticularly useful in cutting longitudinally the Weber an I-beam or H column, or in making long cuts in plates with a shape cutting machine; but the invention is not limited to such applications.

In welding operations, distortion has heretofore been prevented or minimized by preheating the parts to be welded, by applying a wet pack to the parts, or by applying a stream of cooling fluid to each part adjacent the point of welding. Such operations, however, have had as their principal function prevention of buckling, since the weld itself holds the parts together. So far as is known, however, noattempts have been made in the past to prevent distortion of metal which is undergoing a flame cutting operation. In performing a cutting operation, the severed edges are not held together and are accordingly free to become distorted in three dimensions immediate y after being severed. It will be apparent that in making long cuts, as in cases where metal of great length is being cut, say fourteen feet or over, distortion of the metal may attain undesirable proportions.

One object 'of the invention, therefore, is to control or prevent distortion of metal parts as they are being severed by flame cutting. Another object is the provision for this purpose of an apparatus which may be easily carried by a cutting ma chine and which may operate therewith. A further object is the provision of suchapparatus in simple, rugged, convenient, and easily maintained form.) Other objects and the novel features of the invention will be apparent'from the present specification.

The invention is illustrated, for simplicity, in its application to cutting metal plates in the ac companying drawing, in which: a

Fig. 1 is a rear view'of a cutting'machiheto whichapparatus in accordance with the invention has been applied; l

- Fig. 2 is a fragmental horizontal section taken on'theline 11-11 of Fig. 1; i

Fig. 3 is an elevation sl owlng another-form of Fig. 4 is a view of the form of. the invention shown in Fig. 3. as seen from below. i

In accordance with theinvention, a coolingspray is applied to the metal immediately adjacent the cutting nozzle and concurrently with thecutting operation. This spray cools the metal immediately after it is out. No time is therefore allowed for highly heated metal to become disto'rted, and to produce severed parts which may not be usable. p

In the embodiment illustrated in Figs. 1 and 2, there is shown a self-propelled cutting machine M supported on a platel? in well known manner. 5 The cutting machine M carries, in known or convenient-manner, a cutting nozzle N substantially vertically and in a position to project a Jet of cutting fluid or oxidizing gas downwardly from its lower end upon portions of the plate P heated m to an ignition temperature so as to'make a cut K therein. A spray condult or cooling fluid nozzle 0 is disposed transversely behind the cutting nozzle N adjacent its lower end, the position of the spray conduit being substantially horizontal 15 and at right angles to the axis of the cutting nozzle. The spray conduit is perforated on its under side in order thatit may project a cooling fluid downwardly upon the plate P. If the apparatus, in the position shown in Fi 1, be moved in the direction away from the observer, the cut.- ting nozzle N may be caused to flame-cut the plate beneath it along a path which is determined by the direction'in which the cutting machine M moves. At the same time, the spray conduit 0 may be caused to project a spray of cooling fluid immediately behind and across the path of the cutting nozzle N,-thus cooling at once the cut edges on either side of the cut K and preventing their distortion.

Although any appropriate cooling fluid may be employed, for convenience the cooling fluid used wil be referred to hereafter as ,water. Water, or a similarly inert cooling fluid, is particularly efllcacious in that it will not combine with the highly heated metal of the walls of the cut or kerf K. Also, an inert cooling fluid such as 1 water will not combine chemically with the fuel or. combustible gas of the preheating flame or flames which are normally used to assist in main taining the metal in the cutting zone at the desired high temperature.

The gases used by the blowpipe nozzle N are carried thereto by a plurality of tubes in, the fuel gas and the combustion-supporting gas for u the peheatinz flames being mixed'in 'a'mixer. ii immediately adjacent the nozzle N. A'water supply tube I2 having a control valve i3 therein ,is attached to the assembly, as by a bracket 7 ll .fastened'to oneof the tubes i0, and terminates w in the spray conduit C which it is adapted to supply with water.

The spray conduit C is of sufllcient length to extend an appreciable distance on either side of the cutting nonle N, and has a series of openings chemically a a which the nozzle N often this direction openings l5 IS on its under side (see Fig. 2) for projecting the cooling water thereinupon the cut edges of the Plate P.

The operation of the apparatus will be at once apparent. When the usual heating jets have brought the plate P-to ignition temperature, the cutting-fluid valve is opened and the nozzle projects a jet of cutting fluid upon the plate starting the cut K therein. The cooling water control valve i3 is then openedand cooling water, passing through the supply tube l2, enters the spray conduit C and is l5 upon the plate P immediately behind the cut:- ting nozzle N. The cutting machine M is then started and the cut K is continued over i any chosen path along the plate P. At the same time the spray of cooling water is constantly projected upon both of the cut edges at right angles to the cut and immediately behind the cutting 1st,

thereby cooling the edges as soon as they have been cut and preventing distortion thereof.

In the form of the invention which is illustrated in Figs. 3 and. 4, there is shown a nozzle N attached to a shape-cutting In this embodiment, the nozzle N is surrounded at the proper elevation by an annular spray conduit C. "Water is carried to the spray conduit by a supply tube i2, which is, in fact, a continuation of the conduit C. The supply tube I2 is fastened to the blowpipe by means of a bracket l4; and a valve IS in the tubecontrols the flow of water to the spray conduit C. The. conduit C has in its lower side a series of such as those which are provided in the conduit C. These perforations permit the spray conduit to project a spray of cooling water downwardly against the metal as it is cut. The annular pipe or spray conduit C is of peculiar advantage in connection with a shape-cutting machine, since no matter what the direction in is moved and no matter how may be changed. the annular spray conduit will always project a spray of cooling water upon the metal immediately after it is cut, thereby achieving an important object of the invention.

In each of the embodiments which are illustrated, the perforations in the spray conduit have their axes parallel to the major axis of the cutting nozzle. As a result, the jets are projected from c spray conduits in a direction substanparallei to that of the blowpipe jet. It is accordingly possible to position the spray conduit exceedingly close to the nozzle in all cases and to project the spray upon the metal in close proximity to the cutting jet'without interfering o for projecting a spray of water. Furthermore, it.

with the cutting action or the nozzle.

From the foregoing, it will be apparent that the invention provides simple, rugged, durable and easily maintained equipment whereby distortion of the work may beprevented by means of a cooling spray. l urthernrore. the action of the spray is always properly related to that of the blowpipe the nozzle necessarily provides at the same time a corresponding change .in theposition of the spray conduit 0 or C.

Clearly, the apparatus is not necessarily used is to be appreciated that the forms of the invenprojected through the openings nomle, since change in the position of tion here illustrated and described, and the method here described for preventing distortion, are presented merely to indicate how the invention may be applied. Other forms and other methods diil'ering in detail, but not in substance, from those here disclosed will, of course, readily suggest themselves to those skilled in the art.

I claim:

. l. A method of preventing distortion of work being cut by a blowpipe, said method comprising projecting a spray of cooling water substantially at right angles to the cut and immediately behind the cutting jet.

2. A method of preventing distortion of work being 'cut by a blowpipe, said method comprising projecting a spray of cooling water upon the work immediately surrounding the cutting jet.

3. A method of controlling the distortion of a metal body severed by oxy-acetylene cutting, such method comprising directing an inert cooling liquid such as water onto said metal body adjacent the point of cutting so as to retard the flow of heat to portions of said body spaced from the point of cooling, said inert cooling liquid being adapted to efiect cooling of portions of said body without combining chemically with the combustible gas of the preheating flame and also being adapted to cool the keri produced by cutting without combining chemically with the highly heated metal of the walls of said kerf.

4. Apparatus for controlling distortion of ferrous metal work during flame cutting comprising, in combination, a blowpipe provided with a cutting nozzle adapted to discharge a cutting jet of oxidizing gas against portions of said work heated to an ignition temperature; a nozzle for directing cooling fluid substantially perpendicularly against the surface of the work and near to but spaced from the point of impingement of the cutting jet, such cooling fluid nozzle having in the underside thereof a plurality of fluid discharge openings disposed in staggered relation and in a-;;p'lurality of rows for directing a plurality'of closely adjacent jets of cooling fluid against said surface; and means forsupplying a cooling fluid to said cooling fluid nozzle.

5.v In apparatus for cutting ferrous metal work, the combination of a blowpipe provided with a cutting nozzle adapted to discharge a cutting jet of oxidizing gas against portions of said work ,x heated to an ignition temperature; a nomle for directing cooling fluid against an area on such work close to and surrounding the point of impingement of said cutting jet, such cooling fiuid nozzle having in the underside thereof a plurality oi. fluid discharge openings disposed in staggered relation and in a plurality of rows for directing a plurality of closely adjacent jets of cooling fluid against said area of. work: and means for supplying cooling fluid to said cooling fluid nozzle.

6. A method of controlling distortion of ferrous metal work during flame cutting comprising directing abutting jet of oxidizing gas against portions of said work heated to an ignition temperature; and directing a cooling fluidsubstantially perpendicularly againstthe surface of the work and near to but spaced from the point of in a plurality of rows.

' ARTHUR W. DAVIS. 

